No-glue pocketed spring unit construction

ABSTRACT

Methods and systems for no-glue pocketed spring unit construction. Rows of pocketed springs, preferably arranged into modules of more than two pocketed springs surrounding a central hole, are welded together when paired probes and anvils press layers of pocketed spring fabric from the rows of pocketed springs together and a welding pulse of current is transmitted through wires on the probes to heat the wire it is pressed against the fabric. Non-stick material interposed between the wires and the fabric prevents melted fabric from sticking to the wires.

CROSS-REFERENCE

This application is a non-provisional of, and claims priority from, U.S.Provisional App. No. 62/024,451, which is hereby incorporated byreference.

BACKGROUND

The present application relates to methods, devices and systems forno-glue construction of pocketed inner spring units, and moreparticularly to methods and systems for using Joule heating (weldingusing current-heated wire) to construct pocketed inner spring units.

Note that the points discussed below may reflect the hindsight gainedfrom the disclosed inventions, and are not necessarily admitted to beprior art.

Connecting rows of pocketed springs together using a scrim sheetgenerally causes a trampoline-like effect, i.e., compressing springs inone part of the unit pulls on another part of the unit.

Glue connections between pocketed springs generally provide a“crunchier” feeling to a completed pocketed spring unit than connectionsmade by thermal welding.

SUMMARY

The inventor has discovered surprising new approaches to methods andsystems for manufacturing glueless pocketed spring cushioning units foruse in mattresses and other cushioning assemblies. Rows of pocketedsprings preferably comprise multi-pocketed spring modules, springshaving uniform coil diameter, ones of said modules comprising more thantwo pocketed springs welded together to leave a central opening. Rows ofpocketed springs are retained in position by pins, and are transferredto corresponding rows of probes and anvils which pinch layers of fabrictogether and form welds using current passed through heating elements onthe probes.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed inventions will be described with reference to theaccompanying drawings, which show important sample embodiments and whichare incorporated in the specification hereof by reference, wherein:

FIG. 1 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 2 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 3 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 4 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 5 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 6 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 7 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 8 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 9 schematically shows a machine for welding rows of pocketed springmodules to each other.

FIG. 10 schematically shows a machine for welding rows of pocketedspring modules to each other.

FIG. 11 schematically shows an example of a mattress which has a core ofmany pocketed spring units which are mechanically joined togetherwithout glue, using a process like that shown in FIGS. 1-10.

FIG. 12 shows an example of a process for welding rows of pocketedspring modules together.

FIG. 13A schematically shows a sealing head for welding rows of pocketedspring modules to each other.

FIG. 13B schematically shows a sealing head for welding rows of pocketedspring modules to each other.

FIG. 14A schematically shows a probe.

FIG. 14B schematically shows an exploded view of a probe.

FIG. 15 schematically shows an anvil.

FIG. 16 schematically shows a machine for welding rows of pocketedspring modules to each other.

DETAILED DESCRIPTION OF SAMPLE EMBODIMENTS

The present application discloses new approaches to constructingpocketed spring units. In particular, the inventor has developed varioussystems and methods for NO-GLUE construction of pocketed spring units.

The disclosed innovations, in various embodiments, provide one or moreof at least the following advantages. However, not all of theseadvantages result from every one of the innovations disclosed, and thislist of advantages does not limit the various claimed inventions.

-   -   pocketed spring unit construction uses NO GLUE;    -   pocketed spring units, and cushioning assemblies incorporating        pocketed spring units, are more comfortable and        luxurious-feeling;    -   cost-effective welding of entire rows of pocketed springs, or of        an entire cushioning unit;    -   high cushioning unit manufacturing throughput;    -   none of the connections in pocketed spring units are glue        connections;    -   reduced cost of pocketed spring unit construction;    -   reduced cost of pocketed spring unit welding machines;    -   stronger connections between rows of pocketed springs;    -   reduced environmental impact of pocketed spring unit        construction;    -   reduced environmental impact of cushioning assembly construction        and maintenance;    -   rows of pocketed springs, or even an entire cushioning unit, can        be fully welded together in a single weld event, with        controllable vertical weld location, extent, width, and        strength;    -   reduced weight of pocketed spring unit;    -   reduced weight of cushioning assembly;    -   lower cushioning assembly transportation cost per unit;    -   reduced likelihood of unmoored pockets;    -   reduced likelihood of loose springs;    -   increased cushioning unit durability; and    -   enables unitary welds of the full vertical extent of pocketed        spring modules.

The numerous innovative teachings of the present application will bedescribed with particular reference to presently preferred embodiments(by way of example, and not of limitation). The present applicationdescribes several inventions, and none of the statements below should betaken as limiting the claims generally.

The inventor has discovered surprising new approaches to methods andsystems for manufacturing glueless pocketed spring cushioning units foruse in mattresses and other cushioning assemblies. Rows of pocketedsprings preferably comprise multi-pocketed spring modules, springshaving uniform coil diameter, ones of said modules comprising more thantwo pocketed springs welded together to leave a central opening. Rows ofpocketed springs are retained in position by pins, and are transferredto corresponding rows of probes and anvils which pinch layers of fabrictogether and form welds using current-heated wires in the probes.

“Cushioning assembly” and “cushioning unit” are defined herein as anycushioning structure incorporating pocketed springs, e.g., a mattress,couch or cushion.

“Heating element” is used herein to refer to a length of material,preferably a wire (e.g., steel or other metal wire), that willrepeatably produce approximately the same temperature when approximatelythe same current is passed through it for approximately the same amountof time (using Joule heating, also called ohmic heating herein).“Approximately the same” temperature, current and time meaningsufficiently bounded to produce results within tolerances of cushioningunit product requirements and/or specifications.

In preferred embodiments, pockets are formed gluelessly by weldingtogether layers of a flexible material, generally plastic, such as spunbonded polypropylene weighing 1.5 ounces per square yard, using Jouleheating effected by current passed through a heating element compressedagainst the fabric. By forming pockets of a chosen size on a chosenlength and width of fabric, rows of pockets of a chosen length and sizedfor a chosen diameter and length of spring can be produced.

In preferred embodiments, uniform diameter springs are used. Uniformdiameter springs can be manufactured by custom winding high tensilestrength wire with highly uniform shape and thickness.

Some embodiments use or include microcoil springs, which are smallsprings suitable for use in pocketed spring units incorporated into, forexample, upholstery.

Springs are inserted into pockets to form pocketed springs. Springs canbe inserted into pockets oriented horizontally through a seam on top ofthe pocket, and then beaten until they reorient vertically. Generally,this results in a pocketed spring that, in a completed cushioningassembly, can only be oriented in a single direction. For example, a bedmade in this way is typically called “one sided”.

Preferably, springs are inserted oriented vertically through a seam onthe side and allowed to expand to fill the pocket.

Pockets can be fashioned to be shorter than an uncompressed spring, sothat pocketed springs are constantly under load (“preloaded”). Thisgenerally increases the useful lifetime of the spring, by allowing itsspring constant to remain higher, for longer. Preloaded springs aregenerally inserted vertically compressed, and allowed to expandvertically to fill the pocket.

A row of pocketed springs, in which pocketed springs are connected toadjacent pocketed springs (e.g., by the same fabric that forms thepockets) can be formed as shown and described in, for example, U.S. Pat.No. 6,260,331.

Rows of pocketed springs can be fashioned into rows of multi-pocket“modules”, comprising more than two—preferably, four—pockets weldedtogether to leave an opening (a hole) in the middle. Rows of modules canthen be welded together, and those rows can then be welded to each otherto form pocketed spring units. Pocketed spring modules can be assembledas shown and described in, for example, U.S. Pat. No. 6,347,423.Preferably, openings have uniform spacing from each other. This can beaccomplished by, e.g., nearest-adjacent (not catty-corner) springs inmodules having uniform spacing from each other, and modules havinguniform spacing from each other.

Multiple horizontally-adjacent rows of pocketed springs can be connectedtogether to form pocketed spring cushioning units. Generally, pocketedspring units look like arrays of pocketed springs from above.

Springs in completed pocketed spring units are typically compressed veryflat and rolled up into tight cylinders for shipping.

Glue can be used in layers of a cushioning assembly manufactured asdisclosed herein, but preferably is not used in the pocketed springcushioning unit layer(s) assembled using thermal welds.

FIG. 1 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In FIG. 1, the machine is in aninitial position, without pocketed spring modules 200. Two rows ofupward-facing vertical positioning pegs 102 are disposed to penetrateholes 104 in a liftable table 106, are attached to a stable surface 108beneath the liftable table 106, and are configured to hold two rows ofpocketed spring modules 200 in position (see, e.g., FIG. 2). Rows ofpegs 102 are aligned so that a line through a row of pegs 102 isperpendicular to a line between two adjacent pegs 102 in two differentrows. (The left-most row of pegs 102 and row of pocketed spring modules200 in the figures, generally closest to a module 200 entrance side ofthe machine 100, will be called herein the “front-most” rows. Theright-most rows, generally closest to a cushioning unit exit side of themachine 100, will be called the “far-most” rows. Correspondingdirections on the machine are “front-ward” and “far-ward”.)

As shown in FIG. 1, the front row of downward facing phalanges are theprobes 110, and the far-most row of downward facing phalanges are anvils112. Advantageously, the probes 110 and the anvils 112 are spaced atapproximately the same intervals as the upward-facing pegs 102, and arepositioned so that when they are moved (e.g., on a rail system 114, asshown) front-wards to their front-most position, they vertically alignwith the pegs 102.

Probe 110/anvil 112 pairs are configured to compress and heat theplastic fabric of the pockets to a pressure and temperature suitable forwelding together multiple layers (generally two or more layers) of theplastic fabric. Preferably, probes 110 are embodied as shown in FIGS.14A and 14B; anvils 112, as shown in FIG. 15; and sealing heads 300,comprising (inter alia) probes 110, anvils 112, and a rail system 116(or other transport) to open and close them, as shown in FIGS. 13A and13B.

Preferably, the heating element 302 on a probe 110 is located on a long,fabric-facing side of the probe 110 oriented towards a correspondinganvil (as shown, a horizontally-facing side). This simplifies themechanical operation of the probes 110 and anvils 112 inserting into thecentral openings (holes 202) in individual modules 200 and pressingtogether, so that the one or more contact regions 304 on the anvils 112and the heating elements 302 on the probes 110 press together with thespring pocket fabric between, allowing welding in the location(s)corresponding to the contact region(s) 304.

Welding occurs when a probe 110 and an anvil 112 move together(preferably, multiple probe 110/anvil 112 pairs simultaneously), and theheating element 302 in the probe 110 and a facing surface of acorresponding anvil 112 (a contact region 304) press flush against eachother, with the layers of fabric to be welded pressed between them. Theheating element 302 is then activated with a welding pulse at a (1)current, (2) for a time and (3) at an amount of pressure between theprobe 110 and the anvil 112 selected to weld the particular density andthickness of plastic fabric of the pockets to a desired weld strength.The probes 110 and anvils 112 can be pushed together by, e.g., a railsystem 116 (as shown in FIG. 1, a rail system 116 using air actuatorsseparate from the rail system 114 that moves the probes 110 and anvils112 front-ward and far-ward together).

Spacing of pegs 102, probes 110 and anvils 112 can be adjustable tocorrespond to, e.g., module 200 diameter and hole 104 placement.

The table 106 through which the pegs 102 are disposed includes a liftmechanism 120 to push the liftable table 106 upwards; the upward-movingtable 106 pushes upwards rows of pocketed spring modules 200 disposed onthe pegs 102. The lift mechanism 120 shown in FIG. 1 comprises servomotors 122. The table 106 also includes an extractor plate 124,described in more detail with respect to FIGS. 6 and 8.

FIG. 2 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In embodiments as shown in FIG. 2,rows of pocketed spring modules 200 are disposed on, and spatiallyaligned by, the pegs 102. Here, pocketed spring modules 200 comprisefour pocketed springs. Preferably, two rows of pocketed springs arewelded together to form modules 200 prior to the modules 200 beingloaded onto the machine 100, allowing entire rows of modules 200 to betreated as individual, separate units.

Module holes 202 are aligned with pegs 102, and rows of modules 200 aredropped or pushed onto corresponding rows of pegs 102. Advantageously,springs within the pockets are of uniform size, and modules 200 arespaced a uniform distance from each other. Uniform sizing can beadvantageously enhanced by using springs made from high tensile wire ofeven thickness and consistent shape, and by using substantially the samelength of wire to form each coil.

FIG. 3 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. As shown in FIG. 3, the probes 110 andanvils 112 move leftward together to be vertically aligned over the pegs102, and thus also over the holes 202 described by the middles of thepocketed spring modules 200.

FIG. 4 schematically shows a machine for welding rows of pocketed springmodules 200 to each other. As shown in FIG. 4, the liftable table 106has risen, pushing the rows of pocketed spring modules 200 onto thecorresponding probes 110 and anvils 112 and off of the pegs 102.

FIG. 5 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. As shown in FIG. 5, the probes 110 andanvils 112 are pushed together to perform a weld and to move the rows ofmodules 200 to a dropoff position where the probes 110 are aligned overa far row of pegs 102. Preferably, the probes 110 and anvils 112 performa weld while moving the modules into the dropoff position.

As shown in FIG. 5, the probes 110 and anvils 112 push together thefabric between them (and between two corresponding pairs of pocketedsprings in different rows of pocketed spring modules 200). When asuitable pressure has been achieved, a welding pulse of current ispropagated through the heating elements 302 in the probes 110, heatingthe fabric to the point of melting together the layers of fabriccompressed by respective probes 110 and anvils 112. A non-stick materialwith a higher melting point than the fabric (e.g., Teflon, or ahigh-temperature plastic coated with Teflon or a similar material),interposed between the heating elements 302 and the fabric, keeps themelted fabric from sticking to the heating elements 302. The verticalposition of the region(s) where the heating elements 302 in the probes110 and the contact region(s) 304 in the anvils 112 press flush againsteach other during welding generally corresponds to the vertical positionof the weld. Preferably, the heating elements 302 and the contactregions 304 span the entire vertical extent of the plastic fabricbetween the probes 110 and anvils 112.

Generally, the probes and anvils can place welds anywhere along avertical line on the pocket fabric. Further, the strength of said weldsis tunable by controlling the welding pulse current-time curve and theamount of pressure exerted by the probe against the corresponding anvil(with the pocket fabric therebetween). Different numbers, verticalplacements and widths of welds can also be used to control usecharacteristics, such as firmness, of the resulting cushioning unit.

FIG. 6 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In FIG. 6, the probes 110 and anvils112 have moved, pushing the now welded together modules 200 so that theopenings in the frontward row of modules 200 are aligned over the farrow of pegs 102. This places a far edge (or more) of the far row ofpocketed spring modules 200 (as shown in FIG. 6, the row of modules 200currently on the row of anvils 112) under the extractor plate 124.

The extractor plate 124 has holes 126 corresponding to the locations ofthe probe 110 and the anvil 112; as shown in FIGS. 6 and 7, the holes126 partially or fully surround the anvils 112 and/or the probes 110when a front row of modules 200 is in position to be transferred to thefar row of pegs 102.

FIG. 7 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In FIG. 7, the probes 110 and anvils112 have separated and moved back to their original relative position,with the probes 110 now located over the far row of pegs 102.

FIG. 8 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. The liftable table 106 is connectedto, and rises and falls with, the extractor plate 124, which is orientedapproximately parallel to the liftable table 106. When the table islowered as shown in FIG. 8, the extractor plate 124 lowers too, pushingthe now-joined rows of pocketed spring modules 200 off the probe 110 andthe anvil 112, and pushing the holes 202 of the front row of pocketedspring modules 200 onto the far row of pegs 102 (as explained above, theprobes 110 were located over the pegs 102 in FIG. 7). A crank 128 can beused to adjust the height of the liftable table 106 to correspond to theheight of the pocketed spring modules 200.

FIG. 9 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In FIG. 9, a new row of pocketedspring modules 200 has been placed on the front row of pegs 102 bypositioning the holes 202 of the modules 200 over the pegs 102 anddropping or pushing the row of modules 200 onto the pegs 102 (orotherwise inserting the pegs 102 into the holes 202).

FIG. 10 schematically shows a machine 100 for welding rows of pocketedspring modules 200 to each other. In FIG. 10, the probes 110 and anvils112 have moved to vertically align with the front and rear rows of pegs102, respectively. This point in the process corresponds to FIG. 3, butwith one far-most (right-most) row of pocketed spring modules 200already welded to the middle row of pocketed spring modules 200 with anumber of no-glue connections.

FIG. 11 schematically shows a mattress 1300. Generally, a mattress 1300comprises a core 1302, upholstery and a fabric cover (typically calledticking). The core 1302 provides support for a user, upholstery cushionsthe core 1302, and the fabric cover is wrapped around the core 1302 andupholstery and contributes both aesthetics and texture to the surface ofthe mattress 1300.

In preferred embodiments, the core 1302 comprises many pocketed springunits 1304. The upholstery can also comprise pocketed spring units, suchas pocketed microcoil spring units.

FIG. 12 shows an example of a process for welding rows of pocketedspring modules 200 to each other. Pocketed spring modules 200 are loadedonto rows of pegs 102 in step 1400. Paired probes 110 and anvils 112(preferably arranged in rows) are positioned over the pegs 102 toreceive the modules 200 in step 1402. The liftable table 106 then pushesthe modules 200 onto the probes 110 and anvils 112 in step 1404, and theprobes 110 and anvils 112 are pressed closed, with pocket materialpressed between them 1406.

The probes 110 and anvils 112 (preferably still closed together) movethe modules 200 to a dropoff position while welding the rows of modules200 together using a welding pulse through the respective heatingelements 302 in step 1408. Once the dropoff position is reached and theweld is completed, the probes 110 and anvils 112 open (move apart), theprobes 110 are vertically aligned with the far row of pegs 102, and theextractor plate 124 pushes the modules 200 onto the pegs 102 in step1410. Depending on whether the cushioning unit is planned to have morerows of modules 200 welded on (is not complete) 1412, a new row ofmodules 200 is added to the front row of pegs 102 at step 1414, and theprocess repeats from step 1402; or, if welding of rows of modules toform the cushioning unit is complete, then the cushioning unit can beremoved from the assembly mechanism 1416.

Alternatively, if the cushioning unit is complete at step 1412, themodules 200 can be moved to a dropoff position away from the pegs 102,so that the cushioning unit can easily be removed from the assemblymechanism 1418 (this behavior can be built into the assembly mechanism).

FIGS. 13A and 13B schematically show a sealing head 300. Preferably, asealing head 300 comprises a probe 110 with a heating element 302 (seeFIGS. 14A and 14B) that will heat up when current is passed through it;an anvil 112, with a contact region 304 that is preferably detachable toallow reconfiguration (e.g., to one or more contact regions of variedand/or multiple separate vertical extent(s) and/or widths, by whichsize, shape and number of welds generated in a single weld event can beconfigured); and a mechanism for pushing the probe 110 and anvil 112together for a weld, here a set of rails 116 as described above. Asealing head 300 can also include a timer interface 306 to controland/or display the duration of a welding pulse of current, and apressure interface 308 to control and/or display the amount of pressurethe probe 110 and anvil 112 will exert against the fabric during a weld.

FIG. 13A shows the sealing head 300 with the probe 110 and anvil 112 inan open position (the heating element 302 is pointed out, but is notvisible due to probe 110 orientation). FIG. 13B shows the sealing head300 with the probe 110 and anvil 112 in a closed position

FIG. 14A schematically shows a probe 110. FIG. 14B schematically showsan exploded view of a probe 110.

A length of non-stick material 402 (or a length of tape and/or otherstructural material(s) that is coated with non-stick material) overlaysthe heating element 302 (or is otherwise connected to the probe 110 andarranged) so that it is interposed between the heating element 302 andpocket spring fabric of a module 200 when a weld occurs. The non-stickmaterial 402 prevents the heating element 302 from sticking to the(melted) pocket spring fabric. (The heating element 302 is referred toherein as being in “contact” with the fabric during a weld, regardlessof whether non-stick material is interposed therebetween.)

One end of the heating element 302 is connected on each of a top portion404 and a bottom portion 406 of the probe 110 (and to an electricalpower source). The top portion 404 and bottom portion 406 are aligned bymetal bars 408 that insert into holes in the bottom portion 406. Aspring 410 allows the top portion 402 and bottom portion 404 to bepushed apart and pulled together by expansion and contraction of theheating element 302 as a result of heating and cooling. Preferably, thenon-stick material is glued (or otherwise attached) to only one portion,i.e., either the top portion 404 or the bottom portion 406.

In the example embodiment shown in FIGS. 14A and 14B, the probe 110 alsocomprises cover plates 412.

As shown, the heating element 302 wraps around the end of the bottomportion 406 of the probe 110 (the bend in the heating element 302conforms to the shape of the bottom end of the probe 110) to facilitatecontact between the heating element 302 and the full vertical extent ofpocket spring fabric of a module 200, enabling welding of said fullvertical extent in one welding event. Width and thickness of a heatingelement 302 can be selected based on, e.g., width of the probe 110;width and/or depth of the channel 414 (if any) in the probe 110 surfacethat the heating element 302 is disposed in; desired or maximum weldwidth; and desired resistivity (e.g., for temperature and/or efficiencycontrol). Use of a channel 414 in which to recess the heating element302 is preferred, e.g., to help control location and timing of a weld bypreventing contact with and/or pressure of the heating element 302 onpocket spring fabric at a location where (or at a time when) a weld isnot desired (or for a duration longer than desired). As shown, thechannel 414 is defined on an anvil-facing side 416 of the probe 110 bythe cover plates 412.

The body 418 of the probe (at least, the portion near the heatingelement 302 and electrical connections thereto) is preferably made froma poor electrical and thermal conductor (e.g., an insulator), such as G7Garolite (a high-temperature composite).

FIG. 15 schematically shows an anvil 112. The connecting portion 420 ofthe anvil 112 connects to the rest of the sealing head 300. The anvilbody 422 holds a contact region 304. When the anvil 112 and probe 110close together to weld, the contact region 304 presses flush against theheating element 302. The contact region 304 can be made of, for example,rubber.

“Contact region” 304 refers to that portion of the anvil 112 located andshaped to press flush against the heating element 302 in at least onelocation corresponding to a desired weld location on module pocketspring fabric pressed between the probe 110 and anvil 112.

One “welding event” refers to the weld(s) formed by the one or moreprobe 110/anvil 112 pairs that contemporaneously receive a singlewelding pulse of current each, without the probes 110 and anvils 112being removed from the holes 202 of the rows of modules 200 during theperiod of the welding event.

FIG. 16 schematically shows a machine for welding rows of pocketedspring modules 200 to each other.

According to some but not necessarily all embodiments, there isprovided: A method for glueless assembly of cushioning units,comprising: a) inserting one of at least one probe/anvil pair intoopenings in a first continuous row of connected multiple-coil modules,and inserting the other of said probe/anvil pair into openings in asecond continuous row of connected multiple-coil modules, individualones of said modules comprising more than two pocketed springs whichtogether surround one of said openings, individual ones of said pocketedsprings each comprising a spring inside a pocket made of a flexiblematerial; b) moving said probe/anvil pair together such that at leastone contact region on said anvil presses said material against at leastone heating element connected to said probe, and applying current acrosssaid heating element to thereby weld said first and second rows ofmultiple-coil modules together; c) removing at least one of said firstand second rows of modules from said probe/anvil pair; and repeatingsaid steps (a), (b) and (c) until more than two rows of modules havebeen thereby welded together to form a cushioning structure having anextended area.

According to some but not necessarily all embodiments, there isprovided: A mechanism for glueless assembly of pocketed spring units,comprising: at least one probe and at least one anvil, said probe andanvil configured to be inserted into openings in pocketed springmodules, individual ones of said modules comprising more than twopocketed springs which together surround one of said openings, andindividual ones of said pocketed springs each comprising a spring insidea pocket made of a flexible material; said anvil having at least onecontact region configured to press flush against said heating elementwhen said probe and anvil are closed together; and at least one heatingelement mounted on an anvil-facing side of said probe and configured tothermally weld pocketed spring fabric when said probe and said anvilpress together and current is propagated through said heating element.

According to some but not necessarily all embodiments, there isprovided: A method for glueless assembly of cushioning units,comprising: a) inserting multiple double-rows of probe/anvil pairs intoopenings in multiple continuous rows of connected multiple-coil modules,ones of said pairs in ones of said double-rows inserting into openingsin ones of said rows of modules, others of said pairs inserting intoopenings in adjacent ones of said rows of modules, different double-rowsof probe/anvil pairs inserting into different twos of said rows ofmodules; wherein individual ones of said modules comprise more than twopocketed springs which together surround one of said openings, andwherein individual ones of said pocketed springs each comprise a springinside a pocket made of a flexible material; b) moving said probe/anvilpairs together such that said anvils press said material against atleast one heating element disposed along a facing side of correspondingones of said probes, and applying current across said heating element tothereby weld said pairs of rows of multiple-coil modules together; c)removing said pairs of rows of modules from said double-rows ofprobe/anvil pairs; and d) repeating step a) such that said double-rowsof probe/anvil pairs are inserted into different twos of said rows ofmodules that were not welded together in step b), and then repeatingstep b); wherein said rows of modules are sufficient to form a pocketedspring component of a mattress, and whereby said rows of modules arewelded together in two welding events.

According to some but not necessarily all embodiments, there isprovided: A mechanism for glueless assembly of pocketed spring units,comprising: multiple alternating rows of probes and anvils, said probesand anvils configured to be inserted into openings in pocketed springmodules, individual ones of said modules comprising more than twopocketed springs which together surround one of said openings, andindividual ones of said pocketed springs each comprising a spring insidea pocket made of a flexible material; ones of said anvils having atleast one contact region on at least two probe-facing sides, saidcontact regions configured to press flush against said heating elementwhen said probe and anvil are closed together; and at least one heatingelement mounted on each of the anvil-facing sides of ones of said probesand configured to thermally weld pocketed spring fabric when ones ofsaid probes and ones of said anvils press together and current ispropagated through said heating element.

According to some but not necessarily all embodiments, there isprovided: A method for glueless assembly of pocketed spring units,comprising: a) inserting multiple alternating rows of probes and anvilsinto corresponding openings in multiple continuous rows of connectedmultiple-coil modules, individual ones of said modules comprising morethan two pocketed springs which together surround one of said openings,individual ones of said pocketed springs each comprising a spring insidea pocket made of a flexible material; b) moving adjacent pairs of saidprobes and anvils together such that said anvils press said materialagainst at least one heating element disposed along facing sides of saidprobes, and applying current across said heating elements to therebyweld together pairs of modules in said rows of modules; and c) repeatingsaid moving such that said probes and anvils close together with theother adjacent anvil or probe, and repeating said applying current tothereby weld together different pairs of modules in said rows ofmodules.

Modifications and Variations

As will be recognized by those skilled in the art, the innovativeconcepts described in the present application can be modified and variedover a tremendous range of applications, and accordingly the scope ofpatented subject matter is not limited by any of the specific exemplaryteachings given. It is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims.

As used herein and as is apparent from the disclosure set forthhereinabove, “left” and “right” (and “front” and “far”) are arbitraryterms signifying generally opposing directions, respectively orientedtowards pre-weld (generally, welding machine entrance) and post-weld(generally, welding machine exit) pocketed spring module positions asshown in FIGS. 1-10.

In some embodiments, the probes and anvils start in different positionsthan shown in FIG. 1.

In some embodiments, probe/anvil pairs move the rows of modules over toa dropoff position once the modules are fully off of the pegs; in someembodiments, once the modules are fully loaded onto the probe/anvilpairs; in some embodiments, at some (or any) time between.

In some embodiments, a pocketed springs in a row of pocketed springs maybe connected to each other by material other than the material used toform pockets.

In some embodiments, pocketed springs may be formed by welding pocketedsprings to a strip or strips of flexible material (e.g., the materialused to form pockets).

In some embodiments, different lengths or portions of the probe may haveone or more separate heating elements.

In some embodiments, multiple separate heating elements are side-by-sidein a probe.

In some embodiments, rows of pocketed spring modules can beautomatically fed onto rows of pegs.

In some embodiments, rows of pocketed spring modules can be manually fedonto rows of pegs.

In some embodiments, the probes and anvils are moved leftward andrightward together (or separately) by the same transportation systemthat pushes them together and apart for welding.

In some embodiments, lifting mechanisms other than servo motors are usedto lift the liftable table, such as hydraulic motors.

In some embodiments, other transportation types (than rails) and motortypes are used to move the probes left-wards and right-wards, andtogether and apart, than described hereinabove.

In some embodiments, the probe moves to the anvil to press flush againstthe anvil prior to welding.

In some embodiments, the anvil moves to the probe to press flush againstthe probe prior to welding.

In some embodiments, the probe and anvil both move to press flushagainst each other prior to welding.

In some embodiments, probe/probe pairs are used.

The probe is described herein with a particular internal structure thatcompensates for expansion of the heating element during a weld. In someembodiments, the probe has a different structure that compensates forexpansion of the heating element during a weld, e.g., using aflexible/mobile attachment between the heating element and the probe.

In some embodiments, expansion of the heating element is minimized andthe internal structure of the probe is simplified.

In some embodiments, one or more welds is performed as described above;or when the liftable table has not fully transferred the modules to theprobe/anvil pairs; or when a portion of the modules has been pushedabove the top(s) of the heating element(s); or after completetransferal, before, during or after moving the modules to a dropoffposition; or during dropoff; or some or any combination thereof.

In some embodiments in which probes have more than one heating element,different ones of the heating elements can be activated separately.

In some embodiments, the probes and/or anvils push the modules into adropoff position while the probes and anvils are separated from eachother (open).

In some embodiments, something other than the probes and/or anvils(e.g., a pusher rod or plate) moves the modules into a dropoff position.

Particular left/right orientations of the probe and anvil have beendescribed and shown with respect to the disclosed inventions. It will beapparent to one of ordinary skill in the arts of machine engineering ofmanufacturing machinery that alternative orientations of probe/anvilpairs are possible; e.g., reversed orientation (probes switched withanvils); or at +/−30 degrees from the front-ward/far-ward axis of thewelding machine (the latter orientation(s), for example, to weld rows ofhexagonal 6-pocketed spring modules together); or orthogonally to a feedaxis of the welding machine (e.g., to weld disjoint subrows of modulestogether).

It will also be apparent to said person of ordinary skill that doublerows of probe/anvil pairs need not be fully segregated (i.e., that a rowcan consist of both probes and anvils).

In some embodiments, probe/anvil pairs and/or rows of pegs can bearranged otherwise than in orderly rows.

In some embodiments, heating element(s) in a probe and contact region(s)in an anvil are located at, at part of, or including where the probepresses against the anvil (with the fabric between them).

In some embodiments, one or more probe/anvil pairs can be configured toopen and close at different times from other probe/anvil pairs.

In some embodiments, different probe/anvil pairs can be caused to weldat different vertical positions.

In some embodiments, for some welding events, some of the probes, and/orsome of the heating elements in some of the probes, are not transmitteda welding pulse of current.

In some embodiments, probe/anvil pairs can close at different times fromeach other.

In some embodiments, probes have more than two respectively movable,spring-loaded (or similarly movement-restrained) portions.

In some embodiments, different probes can be transmitted differentwelding pulses (e.g., to create different strength welds).

In some embodiments, probes have multiple heating elements in differentvertical locations.

In some embodiments, different heating elements in different probes, orin a single probe, have different widths, lengths and/or resistivities.

In some embodiments, the resistivity of a heating element varies alongits length.

In some embodiments, the resistivity of a heating element varieslaterally (across its width).

In some embodiments, anvils have multiple contact regions in differentvertical locations.

In some embodiments, anvils have multiple contact regions side-by-sidewith each other.

In some embodiments, different contact regions in different anvils, orin a single anvil, have different widths and/or lengths.

In some embodiments, hybrid probe/anvil phalanges, individual phalangeshaving both heating element and contact region portions, can be used. Insome embodiments, a hybrid probe/anvil phalange can have a heatingelement on one side, and a contact region on another (e.g.,opposite-facing) side.

In some embodiments, rather than a pressure switch, an eye or othersensing device is used to determine when to transmit the (current)welding pulse and start the timer for welding pulse duration.

In some embodiments, welding pulse start timing is controlled based onwhen the probe and anvil close together, rather than or in addition to asensing device. Other strategies can also be used to control weldingpulse start timing.

In some embodiments, different vertical positions and extents where aprobe and anvil press flush together can be controlled to be underdifferent amounts of pressure.

In some embodiments, heating elements are coated with a high temperaturenon-stick material. In some embodiments, a high temperature non-stickmaterial overlays, rests upon, is attached to, sheathes, or surrounds aheating element, or otherwise interposes between the heating element andthe fabric during a weld.

In some less preferred embodiments, non-stick material is not used.

Particular up/down orientations have been described hereinabove withrespect to, e.g., the lifting table and extractor plate. It will beapparent to one of ordinary skill in the arts of machine engineering ofmanufacturing machinery that alternative orientations (rather than alonga z axis, or along an axis inverted from that described herein) arepossible.

In some embodiments (and preferably), the springs are in the pocketsprior to welding.

In some embodiments, as will be apparent to those of ordinary skill inthe arts of machine engineering of manufacturing machinery, contactregions on anvils can be made of various materials.

In some embodiments, three or more rows of pocketed springs are weldedtogether substantially simultaneously.

In some embodiments welding three rows of modules together substantiallysimultaneously, for a line of modules containing one module from eachrow, two pairs of probes and anvils perform welds at a given horizontalposition; in other such embodiments, an anvil moves sequentially to twodifferent probes at a given horizontal position; in other suchembodiments, a probe moves sequentially to two different anvils at agiven horizontal position.

In some embodiments, probes have heating elements on both anvil-facingsides. In some embodiments, anvils have contact regions on bothprobe-facing sides. In some such embodiments, one or both exterior (mostfront-ward and most far-ward) rows of probes and/or anvils has heatingelements and/or contact regions on only one side of some or all of theprobes and/or anvils in said row(s).

In some embodiments, two probes or anvils, or a probe and an anvil, areinserted into openings in modules, and rows of modules are welded toboth adjacent rows of modules simultaneously.

In some embodiments, a weld is performed while the probes and anvil aremoving relative to the rows of pegs.

In some embodiments in which the upholstery comprises rows of pocketedmicrocoil springs, the core can be of a type other than pocketedsprings, e.g., continuous coils.

In some embodiments, rows of modules comprise disjoint subrows ofmodules, such that two disjoint subrows of modules are not connected toeach other.

In some embodiments using disjoint subrows of modules, disjoint subrowscomprising a first row are connected to each other when they are weldedto a full row of modules, or welded to a subrow of modules that isdisjoint from other subrow(s) of modules comprising a correspondingsecond row at a location that is not aligned with the disjunction(s) inthe first row.

In some embodiments using disjoint subrows of modules, disjoint subrowsare connected to form a non-disjoint row of modules by welding pocketfabric of disjoint subrows at the location of the disjunction.

In some embodiments, a row of pocketed springs (not modules) isconfigured to be positioned by pegs and welded to another row ofpocketed springs (not modules); for example, using openings described bycylinders (open at top and bottom) or rings formed from excess pocketedspring fabric, or welded onto the rows of pocketed springs. In some suchembodiments, each said row of pocketed springs is itself a doubled rowof pocketed springs.

In some embodiments, the liftable table comprises only sufficientstructure to transfer the rows of modules from the locator pins to theprobe/anvil pairs, or is a continuous structure except where penetratedby locator pins, and can generally be anything between (e.g., a set ofparallel strips, or strips in a criss-cross pattern, or any other shapeor pattern capable of pushing rows of modules from the locator pins ontothe probe/anvil pairs). In some embodiments, rows of modules aresupported by a stationary or separately movable resting table inaddition to or instead of the liftable table when the liftable table isat a position where rows of modules are fully loaded onto the locatorpins (or at a lowest position).

Preferably one “module” of pocketed springs includes exactly fourpocketed springs which totally surround a vertical opening which extendsfor the full height of a pocketed spring. However, in alternative andless preferred embodiments, more or fewer pocketed springs can be usedto define a single module.

In some embodiments, pocketed spring modules comprise pocketed springshaving uniform coil-to-coil distance in a length direction of thecushioning unit, and different uniform coil-to-coil distance in a widthdirection of the cushioning unit.

In some embodiments, a weld is be performed on four or more layers ofpocket fabric, e.g., if the modules are formed from pairs of rows ofpocketed springs welded together, and the rows of pocketed springs arepocketed in pockets formed from a long single sheet of fabric doubledover width-wise.

The pockets which will contain the springs can be formed, for example,from a continuous strip of folded polymer material. Welds are formedacross this strip to separate the pockets from each other. As notedabove, the pockets preferably have openings on their sides where aflattened coil spring can be inserted and released; once the coil springis allowed to expand into the pocket, its ends will stay at the ends ofthe pocket.

Two such strips can then be welded together at every other weldlocation. This produces a strip of modules, where each module includesfour pocketed spring units surrounding an opening. Such a strip ofmodules is shown in FIG. 2 and the following figures.

Optionally the strip of modules can be trimmed to the desired width (orlength) of the finished structure before the steps of FIGS. 1-10 areperformed. However, alternatives are possible, as will be readilyrecognized by those of ordinary skill in the arts of machine engineeringof manufacturing machinery.

In some embodiments, alternative shapes can be used for the extractorplate, such as multiple extractor fingers, or an extractor rod parallelto the table and to the axis formed by a row of modules (i.e., from oneend of the row to the other end of the row).

In some embodiments, a far edge (or more) of a front row of moduleslocated on the probes is under the extractor plate when the front row ofmodules is in position to be transferred to the far row of pegs.

In some embodiments, the extractor plate is shaped to push on differentportions of the front and far rows of modules than described above.

In some embodiments, a manual or automated mechanism other than a crankcan be used to control the height of the table. In some embodiments, acrank or other mechanism can be used to control the height of theextractor plate.

In some embodiments, multiple welds for rows of modules are performedsubstantially simultaneously; in some embodiments, welds for said rowsare (or can be) performed sequentially.

In some embodiments, pockets have insertion slots in the side.

In some embodiments, pocket material is a sheet of flexible polymer.

In some embodiments, coil springs have non-uniform (but known) diameter.

In some embodiments, coil springs have non-uniform (but known) spacingfrom each other.

In some embodiments, all rows of modules are transferred from the pegsto the probes and anvils substantially simultaneously.

In some embodiments, pegs are steel, and have approximatelyfrustoconical tips. In some embodiments, pegs have other conical,prismatic, or otherwise much-longer-than-wide and approximately straightshapes, with tips configured to penetrate modules' central openings(e.g., square prism with a hemispherical tip).

In some embodiments, the liftable table and extractor plate can moveseparately.

In some embodiments, the extractor plate is mechanically connected tothe liftable table at an adjustable distance therefrom.

In some embodiments, probe/probe pairs (both probes havingcurrent-heated wires, which press against each other with fabricbetween) are used to form welds; in which case, probes can be configuredto act as both probes and anvils.

Additional general background, which helps to show variations andimplementations, may be found in the following publications, all ofwhich are hereby incorporated by reference: U.S. Pat. No. 5,772,100;U.S. Pat. No. 3,844,869; U.S. Pat. No. 4,234,983; U.S. Pat. No.4,401,501; U.S. Pat. No. 6,131,892; U.S. Pat. No. 6,260,331; U.S. Pat.No. 6,347,423; U.S. Pat. No. 6,101,697; U.S. Pat. No. 6,021,627; U.S.Pat. No. 5,613,287; U.S. Pat. No. 5,553,443; U.S. Pat. No. 4,439,977;U.S. Pat. No. 4,485,506; U.S. Pat. No. 5,749,133; U.S. Pat. No.5,613,287; U.S. Pat. No. 4,986,518; U.S. Pat. No. 4,906,309; U.S. Pat.No. 4,854,023; U.S. Pat. No. 4,523,344; U.S. Pat. No. 4,234,984; U.S.Pat. No. 3,251,078; U.S. Pat. No. 2,540,441; U.S. Pat. No. 1,226,219;U.S. Pat. No. 1,192,510; and U.S. Pat. No. 685,160; and published U.S.patent applications 20120311784, 20120091644, 20110191962, 20110107572,20100218318, 20100212090, and 20080245690.

Additional general background, which helps to show variations andimplementations, as well as some features which can be implementedsynergistically with the inventions claimed below, may be found in thefollowing US patent applications. All of these applications have atleast some common ownership, copendency, and inventorship with thepresent application, and all of them, as well as any material directlyor indirectly incorporated within them, are hereby incorporated byreference: U.S. Pat. No. 6,131,892; U.S. Pat. No. 6,260,331; U.S. Pat.No. 6,347,423; and U.S. patent application Ser. No. 14/158,811.

None of the description in the present application should be read asimplying that any particular element, step, or function is an essentialelement which must be included in the claim scope: THE SCOPE OF PATENTEDSUBJECT MATTER IS DEFINED ONLY BY THE ALLOWED CLAIMS. Moreover, none ofthese claims are intended to invoke paragraph six of 35 USC section 112unless the exact words “means for” are followed by a participle.

The claims as filed are intended to be as comprehensive as possible, andNO subject matter is intentionally relinquished, dedicated, orabandoned.

1-26. (canceled)
 27. A mechanism for glueless assembly of pocketedspring units, comprising: multiple alternating rows of probes andanvils, said probes and anvils configured to be inserted into openingsin pocketed spring modules, individual ones of said modules comprisingmore than two pocketed springs which together surround one of saidopenings, and individual ones of said pocketed springs each comprising aspring inside a pocket made of a flexible material; ones of said anvilshaving at least one contact region on at least two probe-facing sides,said contact regions configured to press flush against said heatingelement when said probe and anvil are closed together; and at least oneheating element mounted on each of the anvil-facing sides of ones ofsaid probes and configured to thermally weld pocketed spring fabric whenones of said probes and ones of said anvils press together and currentis propagated through said heating element.
 28. The mechanism of claim27, wherein probes are configured to close together with adjacent anvilsand weld pairs of modules from pairs of multiple continuous rows of saidmodules, and then to close together with other adjacent anvils and weldpairs of modules in different pairs of said rows of modules.
 29. Themechanism of claim 27, wherein the front-most row and/or the far-mostrow of said probes and/or said anvils have heating elements and/orcontact regions on only one side.
 30. The mechanism of claim 27, whereinsaid alternating rows can comprise either rows of probes and rows ofanvils, or rows comprising both probes and anvils.
 31. The mechanism ofclaim 27, wherein said heating element wraps over a top edge and/or abottom edge of ones of said probes and a vertical extent of said heatingelement extends to at least one edge of said modules.
 32. The mechanismof claim 27, wherein said heating element extends the full verticallength of said modules.
 33. The mechanism of claim 27, furthercomprising at least one of a pressure switch controlling when saidpropagation of said current begins, and a timer controlling a durationof said current propagation.
 34. The mechanism of claim 27, wherein onesof said probes further comprise at least two connected, respectivelymovable portions, at least two of said portions connected to saidheating element, said portions configured to move apart when saidheating element expands, and move together when said heating elementcontracts.
 35. The mechanism of claim 27, wherein said heating elementis recessed within a channel on said anvil-facing side of said probe,and said contact region is configured to press said material into saidchannel.
 36. The mechanism of claim 27, wherein probes and anvilscomprise at least one heating element on one side and at least onecontact region on another side, are not respectively required to have atleast two heating elements or at least two contact regions, and areconfigured to press said heating elements against said contact regionsand to thermally weld said fabric when current is propagated throughsaid heating element.
 37. A method for glueless assembly of pocketedspring units, comprising: a) inserting multiple alternating rows ofprobes and anvils into corresponding openings in multiple continuousrows of connected multiple-coil modules, individual ones of said modulescomprising more than two pocketed springs which together surround one ofsaid openings, individual ones of said pocketed springs each comprisinga spring inside a pocket made of a flexible material; b) moving adjacentpairs of said probes and anvils together such that said anvils presssaid material against at least one heating element disposed along facingsides of said probes, and applying current across said heating elementsto thereby weld together pairs of modules in said rows of modules; andc) repeating said moving such that said probes and anvils close togetherwith the other adjacent anvil or probe, and repeating said applyingcurrent to thereby weld together different pairs of modules in said rowsof modules.
 38. The method of claim 37, wherein pressure applied by saidprobe/anvil pair to said flexible material is different for differentvertical extents of said flexible material.
 39. The method of claim 37,wherein at least one of the following characteristics of said heatingelement and/or said contact region is selectable: conductivity, verticalextent, vertical location, width, lateral location, number, resistivityof said heating element, and thickness of said contact region.
 40. Themethod of claim 37, wherein adjacent modules are welded together in bothlength and width directions of the cushioning unit.
 41. The method ofclaim 37, wherein said multiple rows of probes and anvils perform stepb) substantially simultaneously.
 42. The method of claim 37, wherein anon-stick material is disposed between said heating element and saidflexible material.
 43. The method of claim 37, wherein said heatingelement is recessed within a channel on said probe, and said contactregion is narrower than said channel.
 44. The method of claim 37,wherein said heating element and said contact region press together andweld along the full vertical extent of said module in a single weldingevent.
 45. A cushioning unit manufactured by the method of claim
 37. 46.The method of claim 37, whereby a mattress-sized cushioning unit isformed from said rows of modules using two welding events.